Sprayable abrasive cleaning compositions

ABSTRACT

A spraying device comprising a reservoir and a nozzle linked by a path is used to apply an aqueous cleaning composition to a surface. The interim dimension of the path is located immediately upstream of the nozzle. The composition comprises abrasive particles, wherein substantially none of the particles has a maximum dimension which is more than half of the minimum dimension of the path and none of said particles have a dimension greater than said minimum dimension.

BACKGROUND OF THE INVENTION

This invention relates to the cleaning of surfaces and more particularlyis concerned with the cleaning of surfaces using compositions containingabrasive particles.

Cleaning compositions containing abrasive particles are well known andmay generally be classified into two types. The first type containwater-insoluble abrasive particles. These particles are often difficultto rinse away from the cleaned surface and can leave an undesirablegritty residue on the surface. In order to overcome these disadvantages,the second type of composition has been proposed in which the abrasiveparticles are water soluble. These compositions contain thewater-soluble abrasive particles in an amount greater than that requiredto achieve a saturated solution. Thus, undissolved abrasive particlesare always present in the composition. Because the abrasive particlesare water soluble, particles remaining on the surface after cleaningtend to be dissolved on rinsing the surface and are thus removed fromthe surface. Cleaning compositions containing water soluble abrasiveparticles are described in EP 0 193 375 and WO 91/08282.

Cleaning compositions of this general type are particularly suitable forcleaning hard surfaces especially in kitchens and bathrooms such assinks, ceramic hobs, washbasins, baths, shower trays and shower stalls,lavatories, work surfaces and the like.

Conventionally, such general cleaning compositions are marketed incontainers formed of flexible plastics material so that the compositionscan be ejected, from the container, by squeezing it.

Attempts have been made to apply abrasive cleaning compositions to asurface to be cleaned by means of a spraying device (trigger).Generally, however, these attempts have not been successful because thenozzle of the spraying device tended to become blocked by the abrasiveparticles.

It is an object of the present invention to provide a sprayable abrasivecleaning composition and a spraying device therefor.

SUMMARY OF THE INVENTION

According to the present invention there is provided a spraying deviceincluding a reservoir containing a cleaning composition comprisingabrasive particles and an aqueous vehicle liquid; a nozzle through whichthe composition can be sprayed on actuation of the spraying device; anda path for enabling the composition to pass from the reservoir to thenozzle, substantially none of the abrasive particles having a maximumdimension which is more than one half of the minimum dimension of thepath and none of the particles having a dimension greater than saidminimum dimension.

By“substantially none” there is meant not more than 4%, by weight, andpreferably not more than 2%, by weight.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a part of one embodiment of a sprayingdevice for use in the combination of the invention.

FIG. 2 is a cross section through a part of the device shown in FIG. 1on an increased scale.

FIG. 3 is a cross section through another part of the device shown inFIG. 1 on an increased scale.

FIG. 4 is a view of the part shown in FIG. 3 from the direction A on areduced scale.

DETAILED DISCLOSURE

Advantageously, the minimum dimension of the path is in the form of aminimum restriction located immediately upstream of the nozzle since, inthis way, an improved spray pattern of the composition can be obtained.This restriction has the function of increasing the velocity of thecomposition and breaking it up into a spray rather than a single jet ofcomposition. Such is particularly important with high viscositycompositions.

Commonly, the size distribution of the particles is such that the meansize is closer to the maximum size than would normally be the case inaccordance with a normal Gaussian distribution.

Typically, the composition may include from 1 to 60% by weight ofabrasive particles and preferably from 1 to 40% by weight. Mostpreferably, the content of abrasive particles is from 5 to 30% byweight.

Suitable examples of abrasive particles are silicon dioxide, aluminiumoxide, polishing earth, calcium carbonate, dicalcium phosphate, ironoxide, magnesium silicates, calcium pyrophosphate, diatomaceous earth(Kieselguhr) and sodium metaphosphate.

In general, water insoluble abrasives are preferred. However, ifdesired, water soluble abrasives such as alkali metal carbonates,bicarbonates and sulphates may be used. Preferred water soluble abrasiveparticles include sodium bicarbonate, sodium tripolyphosphatepentahydrate, sodium tetraborate decahydrate, potassium sulphate andsodium citrate. Additionally or alternatively, other water soluble saltsmay be included, such as sodium chloride, potassium chloride, magnesiumchloride, calcium chloride and other inorganic or organic water solublesalts of lithium, magnesium, sodium, potassium, and calcium, of whichsodium oxalate, sodium succinate, sodium adipate and sodium glutarateare examples.

The water soluble abrasive particles must be present in an amount inexcess of the saturation solubility, so that in the composition thesoluble salt comprising the abrasive particles is present in both thedissolved and the undissolved state. Preferably, the water soluble saltis present in total in an amount of 15% to 60% by weight, particularly30% to 50% by weight, and especially about 40% by weight of thecomposition.

One of the criteria used in selecting the abrasive particles is thehardness of the particles. The particles should have a hardness lessthan that of the surfaces to be cleaned, in order to avoid scratchingthe surfaces. Thus, the particles will usually have a hardness less thanthat of the plastics materials, for example acrylics, conventionallyused for baths and like. A Mohs hardness of at least 2 and less than 4,preferably less than 3 will in general be suitable. For specificapplications, particles of higher hardness can be used.

It is important that the compositions of the invention are stable in useand storage so that the abrasive particles remain in suspension. It mayusually be expected that the compositions will be stored and used attemperatures generally within the range of 0° C. to 40° C. It istherefore preferable, where soluble abrasive particles are used tochoose salts whose saturation solubility changes to the minimum extentover this temperature range. Particularly, it is preferable that thesaturation solubility of the salt in water at 40° C. is less than 10times, most preferably less than 8 times, and especially less than 2times that at 10° C.

To ensure that the composition contains undissolved abrasive particles,the salt forming the abrasive particles will preferably have asaturation solubility at 10° C. of not more than 15% by weight. In orderto ensure that the abrasive particles may easily be rinsed from thesurface after cleaning, the salt will preferably have a solubility inwater of at least 5 g/l at 10° C.

The composition may include additional components such as one or more offrom 0.1 to 15% by weight of a surfactant, from 0.1 to 6% by weight of athickening/suspending agent, up to 30% by weight of an organic solvent,up to 4% by weight of an antibacterial agent, up to 2% by weight of aperfume and up to 5% by weight of a silicone.

Suitable surfactants are anionic, non-ionic, amphoteric and cationicsurfactants.

Suitable nonionic surfactants which can be used in the instant inventioninclude water soluble nonionic surfactants, many of which are well knownand conventionally used in the art. Nonlimiting examples of nonionicsurfactants which may be employed in the composition include those whichare water soluble or water miscible and include one or more of thefollowing: amine oxides, block copolymers, alkoxylated alkanolamides,ethoxylated alcohols, and ethoxylated alkyl phenols, and the like. Othercommercially available nonionic surfactants may be found in the“ChemicalClassification” section of McCutcheon's Emulsifier & Detergents NorthAmerican Edition, 1991 and also in Surfactants Europa, 3rd edn, Hollis(Ed) 1995.

Useful water soluble nonionic surfactants in the compositions accordingto the present invention include commercially well known surfactantcompositions, including the primary aliphatic alcohol ethoxylates,secondary aliphatic alcohol ethoxylates, alkylphenol ethoxylates andethylene-oxide-propylene oxide condensates of primary alkanols. Thesewater soluble nonionic surfactants are generally the condensationproducts of an organic aliphatic or alkyl aromatic hydrophobic compoundand hydrophilic ethylene oxide groups. Practically any hydrophobiccompound having a carboxy, hydroxy, amido, or amino group with a freehydrogen attached to the nitrogen can be condensed with a hydrophilicgroup containing an ethylene oxide and/or the polyhydration productthereof, polyethylene glycol, to form a water soluble nonionicsurfactant.

Useful nonionic surfactants include the condensation products of ahigher alcohol (e.g. an alkanol containing about 8 to 18 carbon atoms ina straight or branched chain configuration) condensed with about 5 to 30moles of ethylene oxide, for example, lauryl or myristyl alcoholcondensed with about 16 moles of ethylene oxide, tridecanol condensedwith about 6 to 10 moles of ethylene oxide, myristyl alcohol condensedwith about 10 moles of ethylene oxide per mole of myristyl alcohol, thecondensation product of ethylene oxide with a cut of coconut fattyalcohol containing a mixture of fatty alcohols with alkyl chains varyingfrom 10 to about 14 carbon atoms in length and wherein the condensatecontains either about 6 moles of ethylene oxide per mole of totalalcohol or about 9 moles of ethylene oxide per mole of alcohol andtallow alcohol ethyoxlates containing 6 moles ethylene oxide to 11 molesethylene oxide per mole of alcohol.

A preferred group of the foregoing nonionic surfactants is certainethoxylates presently commercially available under the trade nameNeodol® (Shell Chemical) which are believed to be higher aliphatic,primary alcohols containing about 9-15 carbon atoms, such as C₉-C₁₁alkanol condensed with 8 moles of ethylene oxide (Neodol 91-8), C₁₂₋₁₃alkanol condensed with 6.5 moles ethylene oxide (Neodol® 23-6.5), C₁₂₋₁₅alkanol condensed with 12 moles ethylene oxide (Neodol® 25-12), C₁₄₋₁₅alkanol condensed with 13 moles ethylene oxide (Neodol® 45-13), and thelike. Such ethoxylates have an HLB (hydrophobic to lipophilic balance)value of about 8 to 15 and give good oil/water emulsification, whereasethoxylates with HLB values below 8 contain less than 5 ethylene oxidegroups and tend to be poor emulsifiers and poor detergents.

Additional satisfactory nonionic surfactant compositions include thecondensation products of secondary aliphatic alcohols containing 8 to 18carbon atoms in a straight or branched chain configuration condensedwith 5 to 30 moles of ethylene oxide. Examples of commercially availablenonionic detergents of the foregoing type are those presentlycommercially available under the trade name of Tergitol® (Union CarbideLtd) such as Tergitol 15-S-12 which is described as being C₁₁-C₁₅secondary alkanol condensed with 9 ethylene oxide units, or Tergitol15-S-9 which is described as being C₁₁-C₁₅ secondary alkanol condensedwith 12 ethylene oxide units per molecule.

Other suitable nonionic surfactant compositions include the polyethyleneoxide condensates of one mole of alkyl phenol containing from about 8 to18 carbon atoms in a straight-or branched chain alkyl group with about 5to 30 moles of ethylene oxide. Specific examples of alkyl phenolethoxylates include nonyl phenol condensed with about 9.5 moles ofethylene oxide per mole of nonyl phenol, dinonyl phenol condensed withabout 12 moles of ethylene oxide per mole of phenol, dinonyl phenolcondensed with about 15 moles of ethylene oxide per mole of phenol anddiisoctylphenol condensed with about 15 moles of ethylene oxide per moleof phenol. Commercially available nonionic surfactants of this typeinclude those which are presently commercially available under the tradename of Igepal® (Rhone-Poulenc, Chemicals Ltd).

Also among the satisfactory nonionic surfactants which find use with thepresent inventive compositions are the water-soluble condensationproducts of a C₈-C₂₀ alkanol with a mixture of ethylene oxide andpropylene oxide wherein the weight ratio of ethylene oxide to propyleneoxide is from 2.5:1 to 4.1, preferably 2.89:1 to 3.3:1, with the totalof the ethylene oxide and propylene oxide (including the terminalethanol or propanol group) being from 60-85%, preferably 70 to 80%, byweight. Such surfactants include those which are presently commerciallyavailable under the trade name of Plurafac® (BASF plc). Further usefulwater-soluble condensation products of C₈-C₂₀ alkanol with a mixture ofethylene oxide and/or propylene oxide include those which are presentlymarketed under the trade name Poly-Tergent SL (Olin UK Ltd) series ofnonionic surfactants which are cited to comprise between 5 and 12 molesof oxyethylene per molecule.

Other suitable water-soluble nonionic detergents which are lesspreferred but which are nonetheless useful are those which are marketedunder the trade name Pluronics® (BASF plc). The compounds are formed bycondensing ethylene oxide with a hydrophobic base formed by thecondensation of propylene oxide with propylene glycol. The molecularweight of the hydrophobic portion of the molecule is of the order of 950to 4,000 and preferably 200 to 2,500. The addition of polyoxyethyleneradicals of the hydrophobic portion tends to increase the solubility ofthe molecule as a whole so as to make the surfactant water-soluble. Themolecular weight of the block polymers varies from 1,000 to 15,000 andthe polyethylene oxide content may comprise 20% to 80% by weight.Preferably, these surfactants are in liquid form and particularlysatisfactory surfactants are available as those marketed as Pluronics®L62 and Pluronics L64.

Alkylmonoglyocosides and alkylpolyglycosides which find use in thepresent inventive compositions include known nonionic surfactants whichare alkaline and electrolyte stable. Alkylmonoglycosides andalkylpolyglucosides are prepared generally by reacting a monosaccharide,or a compound hydrolyzable to a monosaccharide with an alcohol such as afatty alcohol in an acid medium. Various glycoside and polyglycosidecompounds including alkoxylated glycosides and processes for making themare disclosed in U.S. Pat. No. 2,974,134; U.S. Pat. No. 3,219,656; Pat.No. 3,598,865, U.S. Pat. No. 3,640,998; U.S. Pat. No. 3,707,535; U.S.Pat. No. 3,772,269; U.S. Pat. No. 3,839,318; U.S. Pat. No. 3,974,138;U.S. Pat. No. 4,223,129 and U.S. Pat. No. 4,528,106.

One exemplary group of such useful alkylpolyglycosides includes thoseaccording to the formula:

R₂O—(C_(n)H_(2n)O)_(r)—(Z)_(x)

where Z is derived from glucose, R₂ is a hydrophobic group selected fromalkyl groups, alkylphenyl groups, hydroxylalkylphenyl groups as well asmixtures thereof, wherein the alkyl groups may be straight chained orbranched, which contain from about 8 to about 18 carbon atoms, n is 2 or3, r is an integer from 0 to 10, but is preferably 0, and x is a valuefrom about 1 to 8, preferably from about 1.5 to 5. Preferably thealkylpolyglycosides are nonionic fatty alkylpolyglucosides which containa straight chain or branched chain C₈-C₁₅ alkyl group, and have anaverage of from about 1 to 5 glucose units per fatty alkylpolyglucosidemolecule. More preferable, are the nonionic fatty alkylpolyglucosideswhich contain straight chain or branched C₈-C₁₅ alkyl group, and have anaverage of from about 1 to about 2 glucose units per fattyalkylpolyglucoside molecule.

A further exemplary group of alkyl glycoside surfactants suitable foruse in the practice of this invention may be represented by formula

RO—(R₁O)_(y)—(G)_(x)Z_(b)

wherein: R is a monovalent organic radical containing from about 6 toabout 30, preferably from about 8 to 18 carbon atoms; R₁ is a divalenthydrocarbon radical containing from about 2 to about 4 carbon atoms; Ois an oxygen atom; y is a number which has an average value from about 0to about 1 and is preferably 0, G is a moiety derived from reducing asaccharide containing 5 or 6 carbon atoms; and x is a number having anaverage value from about 1 to 5 (preferably from 1.1 to 2); Z is O₂M¹,

O(CH₂), CO₂M¹, OSO₃M¹, or O(CH₂)SO₃M¹; R₂ is (CH₂) CO₂M¹ or CH═CHCO₂M¹;(with the proviso that Z can be O₂M¹ only if Z is in place of a primaryhydroxyl group in which the primary hydroxyl-bearing carbon atom,—CH₂OH, is oxidized to form a

group), b is a number of from 0 to 3x+1 preferably an average of from0.5 to 2 per glycosal group; p is 1 to 10, M¹ is H⁺ or an organic orinorganic counterion, particularly cations such as, for example, analkali metal cation, ammonium cation, monoethanolamine cation or calciumcation.

As defined in Formula above, R is generally the residue of a fattyalcohol having from about 8 to 30 and preferably 8 to 18 carbon atoms.Examples of such alkylglycosides as described above include, for exampleAPG™ 325 CS Glycoside® which is described as being a 50% C₉-C₁₁ alkylpolyglycoside, also commonly referred to as D-glucopyranoside,(commercially available from Henkel Ltd) and Glucopon™ 625 CS which isdescribed as being a 50% C₁₀-C₁₆ alkyl polyglycoside, also commonlyreferred to as a D-glucopyranoside, (available from Henkel Ltd).

The nonionic surfactant can be present either singly, or as a mixture oftwo or more nonionic surfactant compounds as defined above.

Suitable anionic surfactants include, but are not limited to: alkalimetal salts, ammonium salts, amine salts, aminoalcohol salts or themagnesium salts of one or more of the following compounds: alkylsulfates, alkyl ether sulfates, alkylamidether sulfates, alkyl arylpolyether sulfates, monoglyceride sulfates, alkylsufonates, alkylamidesulfonates, alkylarylsulfonates, olefinsulphonates, paraffin sulfonates,alkyl sulfosuccinates, alkyl ether sulfosuccinates, alkylamidesulfosuccinates, alkyl sulfosuccinamate, alkyl sulfoacetates, alkylphosphates, alkyl ether phosphates, acyl sarconsinates, acylisethionates, and N-acyl taurates. Generally, the alkyl or acyl radicalsin these various compounds comprise a carbon chain containing 12 to 20carbon atoms.

Further exemplary anionic surfactants which may be used include fattyacid salts, including salts of oleic, ricinoleic, palmitic, and stearicacids; copra oils or hydrogenated copra oil acid, and acyl lactylateswhose acyl radical contains 8 to 20 carbon atoms.

Particularly useful anionic surfactants include the water-soluble salts,particularly the alkali metal, ammonium and alkylolammonium (e.g.monoethanolammonium or triethanolammonium) salts, of organic sulfiricreaction products having in their molecular structure an alkyl groupcontaining from about 10 to about 20 carbon atoms and a sulfonic acid orsulfuric acid ester group. (Included in the term“alkyl” is the alkylportion of aryl groups.) Examples of this group of synthetic surfactantsare the alkyl sulfates, especially those obtained by sulfating thehigher alcohols (C8-C18 carbon atoms) such as those produced by reducingthe glycerides of tallow or coconut oil, and the alkylbenzene sulfonatesin which the alkyl group contains from about 9 to about 15 carbon atoms,in straight chain or branched chain. Especially valuable are linearstraight chain alkylbenzene sulfonates in which the average number ofcarbon atoms in the alkyl group is from about 11 to 14.

Other anionic surfactants herein are the water soluble salts of:paraffin sulfonates containing from about 8 to about 24 (preferablyabout 12 to 18) carbon atoms; alkyl glyceryl ether sulfonates,especially those ethers of C8-C18 alcohols (e.g. those derived fromtallow and coconut oil); alkyl phenol ethylene oxide ether sulfatescontaining from about 1 to about 4 units of ethylene oxide per moleculeand from about 8 to about 12 carbon atoms in the alkyl group; and alkylethylene oxide ether sulfates containing about 1 to about 4 units ofethylene oxide per molecule and from about 10 to about 20 carbon atomsin the alkyl group.

Other useful anionic surfactants herein include the water soluble saltsof esters of α-sulfonated fatty acids containing from about 0 to 20carbon atoms in the fatty acid group and from about 1 to 10 carbon atomsin the ester group; water soluble salts of 2-acyloxy-alkane-1-sulfonicacids containing from about 2 to 9 carbon atoms in the acyl group andfrom about 9 to about 23 carbon atoms in the alkane moiety;water-soluble salts of olefin sulfonates containing from about 12 to 24carbon atoms β-alkyloxy alkane sulfonates containing from about 1 to 3carbon atoms in the alkyl group and from about 8 to 20 carbon atoms inthe alkane moiety.

Particularly preferred alkyl sulfate anionic surfactants useful informing the compositions of the invention are alkyl sulfates of theformula

wherein R is a straight chain or branched alkyl chain having from about8 to about 18 carbon atoms, saturated or unsaturated, and the longestlinear portion of the alkyl chain is 15 carbon atoms or less on theaverage, M is a cation which makes the compound water soluble,especially an alkali metal such as sodium, or an ammonium or substitutedammonium cation, and x is from 0 to about 4. Most preferred are thenon-ethoxylated C12-15 primary and secondary alkyl sulfates.

Exemplary commercially available alkyl sulfates include one or more ofthose available under the tradename RHODAPON® from Rhone Poulenc Co.(Cherry Hill, N.J.), as well as STEPANOL® from Stepan Chemical Co.(Northfield, Ill.). An exemplary alkyl sulfate which is preferred foruse is a sodium lauryl sulfate surfactant presently commerciallyavailable as RHODAPON® LCP from Rhône Poulenc Co., as well as a furthersodium lauryl sulfate surfactant composition which is presentlycommercially available as STEPANOL® WAC from Stepan Chemical Co.

Particularly preferred alkyl sulfonate anionic surfactants useful informing the compositions of the present invention are alkyl sulfonatesaccording to the formula:

wherein R is a straight chain or branched alkyl chain having from about8 to about 18 carbon atoms, saturated or unsaturated, and the longestlinear portion of the alkyl chain is 15 carbon atoms or less on theaverage, M is a cation which makes the compound water soluble,especially an alkali metal such as sodium, or is an ammonium orsubstituted ammonium cation, and x is from 0 to about 4. Most preferredare the nonethoxylated C12-15 primary and secondary alkyl sulfates.

Exemplary, commercially available alkane sulfonate surfactants includeone or more of those available under the tradename HOSTAPUR® fromHoeschst Celanese. An exemplary alkane sulfonate which is preferred foruse is a secondary sodium alkane sulfonate surfactant presentlycommercially available as HOSTAPUR® SAS from Hoeschst Celanese.

Other anionic surface active agents not particularly enumerated here mayalso find use in the present invention.

Solvents usable in the compositions of the present invention may beselected from solvents known in the art, of which volatile silicones,n-paraffins, alcohols, glycol ethers, propylene glycol, dipropyleneglycol, iso-paraffins and amino methyl propanol are particularlysuitable.

An important function of the solvents included in the inventiveformulations is the removal of fat and grease deposits. In principle,any solvent capable of removal of such deposits, which meetsenvironmental and safety requirements and which may stably be includedin the inventive formulations without deleteriously affecting desirableproperties of the compositions, may be included.

It is desirable that at least a portion of the abrasive particles in thecompositions of the invention should be maintained in suspension, inorder to obviate the need for excessive shaking or agitation of thecomposition by the consumer prior to use. To this end, the compositionsof the invention preferably include a thickening agent. The thickeningagent may be such as to provide the composition with a generallyNewtonian viscosity. Preferably, the composition may be provided with astructured rheology, such as a shear thinning rheology, Generally, forcompositions with Newtonian viscosity, the viscosity will be in therange of from 200 to 600 Cps (as measured using a Brookfield DV-IIIviscometer, Spindle CP42). Where the composition has a structuredrheology, the measured viscosity may be considerably higher. Suitablethickeners and rheology modifiers include polysaccharides such ashydroxy celluloses, carboxy methyl celluloses, polyacrylates and otherthickening media known in the art such as natural gums, alginates,silica aerogels, silica precipitates and natural and synthetic clays.

Examples of suitable antibacterial agents are phenolic compounds andcationic bactericides.

Silicones are preferably included to act as an internal lubricant andsuitable silicones are dimethicone and polydimethylsiloxanes.

The spraying device may be, for example, a simple finger pump or anyconventional spraying device either of the type including a simple pumpmechanism or of the type where the material to be sprayed ispre-compressed (such as described in EP-0449046).

Referring now to the drawings, there is shown a spraying devicecomprising a container having a reservoir 15 defined by walls 1 foraccommodating the composition (not shown) and terminating in an openingto which is secured a spraying arrangement generally denoted byreference number 2. The spraying arrangement comprises a nozzle member 3secured in a first end of an actuator extension 4, including a deliverybore 5, which is secured, at its second end, to a delivery head 30including a conduit 6 with which bore 5 is in communication. The conduit6 is in the form of a tube which is located within an outer tubularcasing 7 and axially displaceable with respect thereto. A piston 8 ismounted in sealing engagement with the outer periphery of the conduit 6.The piston 8 is also in sealing engagement with the inner surface ofouter casing 7. Thus axial displacement of the conduit 6 varies thevolume of a chamber 9 defined between conduit 6, casing 7, piston 8, andball 22 of a ball valve. A precompression spring 10 is provided, aroundthe outer surface of conduit 6, and has one end abutting against a firstend of the piston 8 and its other end abutting against a flange 11 onthe outer periphery of the conduit 6. A poppet valve arrangement isprovided at the second end of the piston 8. This comprises a cylindricalbody 12 in the conduit 6 and including an external flange having a firstface abutting against the second end of the piston 8 and a second faceabutting against one end of a spring 13 having its other end fixed tothe internal surface of the casing 7. At its free end, the outer casing7 fits around a dip tube 14 opening into the composition in thereservoir 15. The spraying device includes a hand lever 16 including anabutment 17 which, when the lever 16 is pivoted about pivot point 18 inthe direction shown in arrow B, abuts against one end of a rocking lever19 pivoted about pivot 20 so that another end of the rocking lever 19acts on the delivery head 30 to axially displace the conduit 6 withrespect to the casing 7. The spraying arrangement is enveloped in a cap21.

The nozzle member 3 at the end of the actuator extension 4 comprises acup-shaped body 31 having, in its end wall, a nozzle comprising anorifice 24 of diameter about 500 mm formed in a conically shaped recess25. The recess 25 is in communication with a conduit 26 formed withinthe cup-shaped body 31 by an insert 27. Three tangentially arrangedducts 28 link the conduit 26 with the conical recess 25. Thus there is apath extending between the reservoir 15 containing the composition andthe orifice 24 which path comprises the dip tube 14, the chamber 9, theconduit 6, the bore 5, the conduit 26, the ducts 28 and the recess 25.The conduit 26 has a dimension of 350 mm, and that part of the pathwhich has a minimum dimension is the duct 28 which defines a restrictionof 200 mm. Thus, the smallest restriction is immediately upstream of thenozzle member 3.

In use, the hand lever 16 is actuated in the direction indicted by thearrow B which causes the conduit 6 to be axially displaced downwardlytowards the ball 22. The ball 22 is free to move up and down betweenlower and upper positions. In its lower position it closes the chamber 9from the dip tube 14. In its upper position it allows composition topass from the dip tube 14 into chamber 9. As the conduit 6 is axiallydisplaced in this way, it carries with it the piston 8 due to thepresence of the precompression spring 10. This movement of the piston 8causes a similar movement of the body 10 against spring 13 andcompresses the chamber 9. The air initially in chamber 9 is replaced bycomposition from the reservoir 15 as the lever 16 is actuated. When thepressure in the chamber 9 reaches a critical level set by theprecompression spring 10, it causes the piston 8 to move axially in theopposite direction, overcoming the action of the spring 10 therebyallowing composition under pressure to pass into zone 23 which is incommunication with conduit 6. Thus, when the pressure in the chamber 9exceeds the critical level, composition is forced from the chamber 9 tothe nozzle 24 via consuit 6 and bore 5 of actuator extension 4.

The following Examples illustrate the invention. In these examples, allparts are parts by weight unless there is an indication to the contrary.

EXAMPLE 1

An aqueous abrasive cleaning composition was prepared as follows:

Chalk 10% Sodium lauryl sulphate (28%) 2% Monoethanolamine 0.4%Cyclodimethicone/dimethicone 9% Polydimethysiloxane 0.5% Water 77.9%

The chalk was Fordacal 200 (produced by milling a very pure brightdeposit of crystalline calcium carbonate (55.5% CaO, 43.9% CO₂) and itsparticle size distribution was as follows:

Chalk (Fordacal 200) >5.8 microns 95% >10.5 microns 50.8% >18.9 microns59% >34.1 microns 27% >53 microns 11% >71.4 microns 4.3% >100 microns1.2% >200 microns 0%

The composition could be very satisfactorily sprayed using a sprayingdevice as described in the drawings. More particularly, the nozzle ofthe nozzle member 3 did not become blocked and, moreover, thecomposition emanating from the orifice 24 had a desirable spray pattern.

EXAMPLE 2

An aqueous abrasive cleaning composition was prepared as follows:

Diatomaceous Earth 10% Hydroxyethyl cellulose 1% Sodium lauryl sulphate(28%) 2% Isopropyl Alcohol 5% Ethoxylated Alcohol 3%Polydimethylsiloxane 0.5% Perfume 0.6% Water 77.9%

The particle size distribution of the diatomaceous earth was as follows:

>1 microns 96.8% >5 microns 76.6% >10 microns 50.8% >20 microns15.3% >35 microns 3.0% >50 microns 1.1% >75 microns 0.3% >100 microns0.2% >200 microns 0%

Results similar to that of Example 1 were obtained when the compositionas sprayed through the spraying device shown in the drawings.

EXAMPLE 3

Different grades of Fordacal were made into water based abrasive cleanercompositions comprising 10% of the Fordacal and each was sprayed usingthe spraying device shown in the drawings. As can be seen from thefollowing Table, the range of particles of sizes used varied from a topcut (that is, the maximum size of particles within the particle sizerange as distinct from the average particle size) of 1000 microns to atop cut of only 12 microns.

TABLE MEAN SIZE TOP CUT PRODUCT MICRONS MICRONS SPRAY Fordacal 16 3001,000 NO Fordacal 25 200 750 NO Fordacal 36 150 600 NO Fordacal 60 60200 NO Fordacal 100 25 150 NO Fordacal 200 20 100 YES Fordacal 300 15 75YES Fordacal 45 12 45 YES Fordacal 30 7 30 YES Fordacal 10 2 12 YES

It can be seen that any Fordacal grades with a top cut of smaller thanor equal to 100 microns was successfully sprayed and did not cause thespraying device to fail.

Any grades of Fordacal with a top cut grater than or equal to 150microns did not spray and caused the spraying device to fail.

EXAMPLE 4

To differentiate between the importance of mean particle size and topcut an experiment was carried out where a Fordacal grade that had beensuccessfully sprayed was mixed with a grade that did not spray in theabove test. The grades used were Fordacal 200 (mean particle size 20microns and top cut size of 100 microns) and Fordacal 60 (mean particlesize 60 microns and top cut size of 200 microns). This meant that themean particle size of Fordacal 60 was less than the size of the top cutof Fordacal 200.

In the first embodiment Fordacal 200 was mixed with Fordacal 60 to givea 50%:50% mixture of Fordacal 200 and Fordacal 60.

This mixture did not spray.

In a second experiment Fordacal 200 was mixed with Fordacal 60 to give a75%:25% mixture of Fordacal 200 and Fordacal 60.

This mixture did not spray.

This example suggests that the mean particle size is far less importantthan the top cut size.

What is claimed is:
 1. In combination, (1) a cleaning compositioncomprising abrasive particles and an aqueous vehicle liquid, and (2) aspraying device in which a manually-operated pump provides pressurizedair at a single level of pressure, said device including a reservoiradapted to contain said cleaning composition, a nozzle through which thecomposition can be sprayed on actuation of the spraying device, and apath of varying dimension for enabling the composition to pass from thereservoir to the nozzle, substantially none of the abrasive particleshaving a maximum dimension which is more than one half of the minimumdimension of the path and none of the particles having a dimensiongreater than said minimum dimension.
 2. The combination of claim 1,wherein the location of said minimum dimension is immediately upstreamof the nozzle.
 3. The combination of claim 2, wherein the abrasiveparticles are particles of silicon dioxide, aluminum oxide, polishingearth, calcium carbonate, dicalcium phosphate, iron oxide, magnesiumsilicate, calcium pyrophosphate, diatomaceous earth, sodiummetaphosphate or mixtures thereof.
 4. The combination of claim 2,wherein the abrasive particles are particles of a water soluble salt. 5.The combination of claim 4, wherein the water soluble salt is an alkalimetal carbonate, bicarbonate or sulphate.
 6. The combination of claim 2wherein the composition additionally includes one or more of asurfactant, thickening/suspending agent, an organic solvent, anantibacterial agent, a perfume, or a silicone.
 7. The combination ofclaim 6 in which the cleaning composition comprises a nonionicsurfactant.
 8. The combination of claim 6 in which the cleaningcomposition comprises an anionic surfactant.